Some examples of the poor installation of electrically isolated prestressed ground anchors in Slovenia

Since 1994, when Slovenia's National Motorway Construction Programme began, a total of 85 retaining structures with permanent prestressed ground anchors have been built. Even though the design of all the used anchoring systems was thoroughly reviewed, and the performance of typical installed anchors was verified by means of preliminary field and laboratory tests, some cases of poor installation practice, indicating the possibility of significant corrosion damage to the elements of anchor heads, were discovered. The paper provides a description of the findings of inspections of the most critical anchors of several anchored structures. The poor condition of the investigated anchors can be ascribed mainly to the presence of water beneath the anchor caps and covers as a result of non-watertight fixing. The findings of laboratory tests of samples of the corrosion protection compounds used, i.e. grease and vaseline, are also described.

• Introduction

• Damage to anchors supporting two anchored piled retaining walls, located next to the portals of a tunne

• Damage to anchors of an anchored retaining wall, located next to an exit road from the motorway

• Results of laboratory tests of the samples of grease and vaseline

• Conclusions and recommendations

• Acknowledgements

• References